Thermal and hydraulic performance of ZnO/EG based nanofluids in mini tubes of different diameters: An experimental investigation
Muhammad Ahsan,
Adnan Qamar,
Rabia Shaukat,
Habib-ur-Rehman Siddiqi,
Zahid Anwar,
Muhammad Farooq,
Muhammad Amjad,
Shahid Imran,
Mansoor Ahmed,
M.A. Mujtaba,
H. Fayaz,
Basma Souayeh
Affiliations
Muhammad Ahsan
Department of Mechanical, Mechatronics and Manufacturing Engineering, University of Engineering and Technology Lahore, New-Campus, Pakistan
Adnan Qamar
Department of Mechanical, Mechatronics and Manufacturing Engineering, University of Engineering and Technology Lahore, New-Campus, Pakistan
Rabia Shaukat
Department of Mechanical, Mechatronics and Manufacturing Engineering, University of Engineering and Technology Lahore, New-Campus, Pakistan
Habib-ur-Rehman Siddiqi
Department of Mechanical, Mechatronics and Manufacturing Engineering, University of Engineering and Technology Lahore, New-Campus, Pakistan
Zahid Anwar
Department of Mechanical, Mechatronics and Manufacturing Engineering, University of Engineering and Technology Lahore, New-Campus, Pakistan
Muhammad Farooq
Department of Mechanical, Mechatronics and Manufacturing Engineering, University of Engineering and Technology Lahore, New-Campus, Pakistan
Muhammad Amjad
Department of Mechanical, Mechatronics and Manufacturing Engineering, University of Engineering and Technology Lahore, New-Campus, Pakistan
Shahid Imran
Department of Mechanical, Mechatronics and Manufacturing Engineering, University of Engineering and Technology Lahore, New-Campus, Pakistan
Mansoor Ahmed
ZI Engineering, PC 10 Fifth Street, Third Floor Suite 303, Valley Stream, NY, 44581, United States
M.A. Mujtaba
Department of Mechanical, Mechatronics and Manufacturing Engineering, University of Engineering and Technology Lahore, New-Campus, Pakistan
H. Fayaz
Modeling Evolutionary Algorithms Simulation and Artificial Intelligence, Faculty of Electrical and Electronics Engineering, Ton Duc Thang University, Ho Chi Minh City, Viet Nam; Corresponding author.
Basma Souayeh
Department of Physics, College of Science, King Faisal University, P.O. Box 400, Al-Ahsa, 31982, Saudi Arabia; Laboratory of Fluid Mechanics, Physics Department, Faculty of Sciences of Tunis, University of Tunis El Manar, Tunis, 2092, Tunisia
The present experimental study investigates the thermal and hydraulic performance of Ethylene Glycol (EG)-based ZnO nanofluids (NFs) in circular minichannel test sections, each of 330 mm in length and 1.0–2.0 mm inner diameters. The experiments were conducted under steady-state constant heat flux and laminar flow conditions. The stable ZnO/EG-based NFs were synthesized using a standard two-step method in varying nanoparticles (NPs) loadings (0.012–0.048 wt%). The morphological characteristics, crystal structure, and specific surface area (SSA) showed that the NPs were sized in nm, possessing excellent crystal structure and enhanced surface area. Thermal conductivity (TC) and viscosity (VC) of the NFs were examined in the 20–60 °C temperature range. Both TC and VC possessed an increasing trend with the rise in concentration of the NPs. However, with the temperature rise, TC increased while the VC decreased and vice versa. The highest enhancements in TC and VC were 14.38 % and 15.22 %, respectively, at 40 °C and 0.048 wt% of NPs loading. The highest enrichment recorded in the local and average heat transfer coefficient (HTC) were 14.80 % and 13.48% in a minichannel with 1.0 mm inner diameter, respectively. It was directly proportional to the NPs loading and volume flow rate of the NFs. The friction factor was also directly proportional to the test section's inner cross-sectional area, while the pressure gradient showed an inverse behavior. An inverse relationship was recorded for the volume flow rate of the NFs and vice versa. Maximum friction factor and the pressure drop for all three minichannel test sections were recorded as 34.58 % and 32.16 %, respectively. The well-known Shah correlation predicted the local and average HTC within ±15.0 %, while the friction factor and the pressure gradient were well predicted by the Darcy correlation within the ±10.0 % range.
